This invention relates to the field of game balls. More specifically, this invention relates to a multi-layered game ball product and a process for the manufacture thereof.
Efficient manufacturing processes for game ball products having a single layer are well known. The game ball product can be a finished game ball or form the core of a finished game ball. Game ball products produced of a single layer of a material can display less than optimal characteristics. The material of the single layer typically must be capable of performing several different functions simultaneously. For example, a single layer basketball must be constructed of a material that can form an air-tight bladder. In addition, the same material must provide abrasion resistance for an adequate product life for the game ball product. Furthermore, the same material must have dimensional stability for the game ball product to resist overexpansion as the ball is inflated and is used during the product lifetime. Single layer materials typically cannot provide optimal characteristics for all the performance requirements.
Given these differing operational requirements and deficiencies of a single layer game ball product, it is well known to produce a game ball product having multiple layers of differing materials. Each layer of the multi-layer game ball product is directed to providing a specific function or characteristic for a given performance requirement. For example, a game ball product may be produced of two layers. The outer layer provides abrasion resistance, and the inner layer, such as a bladder, provides an air-tight seal for the game ball product. Multi-layer game ball products therefore typically have superior performance characteristics relative to single layer game ball products. However, multi-layered game ball products typically require additional manufacturing steps compared to the production of the single layered game ball product. Therefore, multiple layered game ball products typically have a higher relative production cost and a more extended production time.
For example, basketballs are conventionally constructed by cold molding or hand laying panels of rubber, leather or synthetic leather onto a basketball carcass. These multi-layer basketballs typically require additional manufacturing steps in comparison to a single layer game ball product.
Single and multi-layer game ball products are also used as game ball cores. Game ball products employed as game ball cores for baseballs and softballs are known to be manufactured of flexible, semi-rigid and rigid polyurethane foam, rotational molded polyolefins, foamed ionomers, cork, kapok and wound string. These conventional game ball cores typically require multiple manufacturing steps in addition to further manufacturing to apply an outer shell to the core. Each additional manufacturing step typically increases final cost of the finished game ball.